Here's a test patch for ixus75 101a for the touch control issue.
For ixus75 and a550, do they not respond at all when your press the power button, or do they power up, but still in play mode, or something else?
Also, for ixus75, can you try
=post_levent_to_ui'TransitFeatherRight'
=post_levent_to_ui'TransitFeatherLeft'
=post_levent_to_ui'TransitFeatherUp'
=post_levent_to_ui'TransitFeatherDown'
in chdkptp
I'm guessing some of these might trigger the effect you get when you circle your finger on the dial.